Food, drug interactions may increase effectiveness of therapy

In collaboration with the Press Association

Cancer researchers have proposed that foods which affect the absorption of anti-cancer drugs may be used to increase the drugs' effectiveness.

Recent studies have shown that certain foods can alter the absorption or slow the breakdown of anti-cancer drugs.

Now, scientists from the University of Chicago have suggested that these drug-food interactions could be used to reduce the costs and increase the effectiveness of medication.

Writing in the Journal of Clinical Oncology, Drs Mark Ratain and Ezra Cohen, oncologists at the University of Chicago, described a recent study by Dartmouth researchers, who conducted tests to determine whether the absorption of the breast cancer drug lapatinib was affected by food.

They found that taking lapatinib with food increased drug absorption by 167 per cent, while eating a high-fat meal increased levels by 325 per cent.

Dr Ratain explained: "Simply by changing the timing, taking this medication with a meal instead of on an empty stomach, we could potentially use 40 per cent (or even less) of the drug.

Dr Ratain calculated that, as lapatinib costs about £1,430, this could save £850 or more per patient a month.

The researchers also suggest that taking the drug with a meal could reduce the frequency and severity of diarrhoea, a common side-effect of cancer treatment which is thought to be caused by unabsorbed medication.

In addition, drinking grapefruit juice after the meal could increase plasma concentrations of the drug, increasing the potential savings to 80 per cent.

"We expect the one 250mg lapatinib pill accompanied by food and washed down with a glass of grapefruit juice may yield plasma concentrations comparable to five 250mg pills on an empty stomach," Dr Ratain added.

The researchers argue that these kinds of interactions could provide a new way to reduce treatment costs and increase the benefits of expensive anti-cancer drugs.

"The rapidly escalating price of medications (especially for cancer and other life-threatening diseases) has provided incentives to explore pharmacological approaches to lower the costs of drugs," they concluded.

"As we enter an era of 'targeted' anticancer agents with a monthly cost measured in thousands of dollars, we should view drug-drug or drug-food interactions as opportunities to lower costs."

Professor Richard Sullivan, Cancer Research UK's director of clinical programmes and centres, said: "This important research demonstrates the value of studying the best way to give a new drug to patients.

"Unfortunately very little research is taking place in this area, but we feel investigations of this type are needed for both reducing the cost to the NHS of prescribing drugs and improving the quality of life for patients who could benefit from shorter treatment programmes."